The widget manufacturing company had established a threshold of 60% preferring the proposed new widget to move forward with producing the new widgets.

This means that at the null hypothesis we test if the proportion is at least 60%, that is:

$H_{0}: p \geq 0.6$

And the alternate hypothesis is:

$H_{a}: p < 0.6$

The test statistic is:

$z = \frac{X - \mu}{\frac{\sigma}{\sqrt{n}}}$

In which X is the sample mean, $\mu$ is the value tested at the null hypothesis, $\sigma$ is the standard deviation and n is the size of the sample.

0.6 is tested at the null hypothesis:

This means that:

$\mu = 0.6$

$\sigma = \sqrt{0.6*0.4}$

Three hundred thirty-eight of 575 respondents reported preferring the proposed new widget.

This means that $n = 575, X = \frac{338}{575} = 0.5878$

Value of the test-statistic:

$z = \frac{X - \mu}{\frac{\sigma}{\sqrt{n}}}$

$z = \frac{0.5878 - 0.6}{\frac{\sqrt{0.6*0.4}}{\sqrt{575}}}$

$z = -0.6$

Pvalue of the test and decision:

We want to find the probability of a proportion of 0.5878 or lower, which is the pvalue of z = -0.6.

Looking at the z-table, z = -0.6 has a pvalue of 0.2743.

Since 0.2743 > 0.1, the threshold probably was met.

3 0

3 years ago

Scott wants to buy fencing to place around a circular rock garden. The diameter of the circle is 16 feet. Using 3.14 for π, Calc

denpristay [2]

Answer:

200.96 square feet

Step-by-step explanation:

The amount of fencing Scott will need to buy can be gotten by calculating the area of the circular rock garden .

Area of a circle is given by

Pi r^2

Where

r = radius

Given diameter of 16 feet

r = diameter/2

= 16/2

= 8 feet

Pi = 3.14

Therefore,

Area = 3.14 x 8^2

= 3.14 x 8 x 8

= 200.96 square feet

The amount of fencing Scott will need to buy is 200.96square feet

5 0

2 years ago